| 摘要 |
The present invention provides an improved way of testing. Named a pointer type automatic tester with storage battery, this apparatus is to replace the hand-operated tester. It is designed to discard the inaccuracy of a test caused by handwork operation due to the different ways of pressing the button and therefore different resistance. With the application of this utility model, the totally programmed test will rule out the manual factors that affect the accuracy of a test. This model is low in cost, practicable, simple, and easy to operate. It contains a start key that is to connect with singlechip. The singlechip is to connect with amplifying circuit and a buzzer. An amplifying circuit is to connect with a relay. The relay has two contacts, one for the connection of negative pole and the other for load resistance. The relay also links with positive pole as well as an optocoupler. And a TVS tube or surge absorber is installed between an optocoupler and a load resistance
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